
<Huawei>display ospf peer last-nbr-down
Neighbor Ip Address : x.x.x.x
Neighbor Area Id : 0.0.0.2
Neighbor Router Id : x.x.x.x
Interface : Vlanif2015 (200)
Immediate Reason : Neighbor Down Due to Kill Neighbor
Primary Reason : BFD Session Down
Down Time : 2018-03-05 03:21+08:00
The status of the non-virtual neighbor has changed. (RouterId=x.x.x.x, NbrIpAddress=x.x.x.x, NbrAddressLessIndex=0, NbrRtrId=x.x.x.x, NbrState=1, ProcessId=5, AreaId=0.0.0.2, IfnetIndex=217, LocalIfIpAddress=x.x.x.x, IfName=Vlanif2034, VpnName=vpn-sigtran, Reason=BFD session state change, SubReason=BFD Session Down)

1. With command display bfd running-info session command, it shows that the reason of bfd down is local down, and the local down because of didn’t receive bfd from peer device.
2018-03-05 03:21:695 FEI notify.(MD=16408,YD=16396,CfgTX=100,CfgRX=100,CfgDM=3,ActTX=200,ActRX=200,ActDM=3,State=3,P=0,F=0)
2018-03-05 03:21:695 FEI notify session DOWN.(MD=16408,YD=16396,Diag=1,Seq=16973569)
2018-03-05 03:21:695 Session DOWN.(MD=16408,YD=16396,Dia=1,Reason=0,State=3,FeiDownCount=1)
2018-03-05 03:21:697 Notify App(0x8204be):State=1,SubState=0x40000.
2018-03-05 03:21:715 FEI notify.(MD=16440,YD=16392,CfgTX=100,CfgRX=100,CfgDM=3,ActTX=200,ActRX=200,ActDM=3,State=3,P=0,F=0)
2018-03-05 03:21:715 FEI notify session DOWN.(MD=16440,YD=16392,Diag=1,Seq=16973569)
2. Checking the configuration, BFD detect interval is 3*100ms, it is too short, recommend set to 3*1s.
interface Vlanif2013
ip binding vpn-instance vpn-sigtran
ip address x.x.x.x 255.255.255.240
ospf dr-priority 100
ospf bfd enable
ospf bfd min-tx-interval 100 min-rx-interval 100

BFD detect interval is 3*100ms, it is too short, recommend set to 3*1s.

Set BFD detect interval to 1s
interface Vlanif2013
ospf bfd min-tx-interval 1000 min-rx-interval 1000

On CE switch, BFD process by software, the recommand detect interval is 3*1s.